Artificial humeral head replacement

The humeral head is actually the upper arm of the human body. The strength of each artificial bone is different. Some people's humeral head is prone to humeral head fractures after being hit by external force, and in severe cases, the humeral head may also be broken. When the humeral head is comminuted, artificial femoral head replacement surgery is required. What is the process of artificial humeral head replacement surgery?

Artificial humeral head prosthesis replacement is a medical method used for proximal humeral comminuted fractures, etc.

Indications

Artificial humeral head replacement is suitable for:

1. Consolidation of proximal humeral comminuted fractures. Proximal comminuted fractures are difficult to reduce. Due to interruption of blood supply, some free bone fragments will become necrotic and require artificial humeral head replacement, including: "four-piece" proximal humeral fractures with displacement or dislocation; proximal humeral compression fractures with more than 40% collapse of the articular surface; and humeral head splitting.

2. Osteoarthritis There is still controversy over whether to choose artificial humeral head replacement or total shoulder replacement for osteoarthritis, and each has its own advantages and disadvantages. Clinical studies have shown that when the glenoid fossa is still concentric and there is no anterior or posterior damage, artificial humeral head prosthesis replacement can be successful. However, when the glenoid fossa is flat and damaged and the humeral head is subluxated posteriorly, the results of artificial humeral head prosthesis replacement are unsatisfactory. 3. Rotator cuff tear arthropathy Although total shoulder replacement can significantly relieve pain and improve function and motion in patients with irreparable rotator cuff tear, long-term follow-up studies have shown that loosening of the glenoid prosthesis is related to irreparable rotator cuff tear. Artificial humeral head prosthesis replacement can significantly relieve pain in about 75% of patients with glenohumeral arthritis and severe rotator cuff dysfunction, and also achieve certain improvements in motor function and muscle strength. It is currently agreed that patients with poor glenoid bone quality, irreparable rotator cuff tears, and avascular necrosis of the humeral head but normal glenoid articular surface should undergo artificial humeral head prosthesis replacement.

Restrictive prostheses are prone to loosening and breaking and are rarely used nowadays, except occasionally in salvage surgeries. Semi-restrictive prosthesis consists of 2 to 3 parts, with joints composed of metal on high molecular polyethylene material. The joints can be connected by locking pins or occlusal matching devices. Semi-restrictive hinge prosthesis has inherent valgus and varus laxity, which is conducive to dispersing external forces, such as Goonrad-Morrey prosthesis. Non-restrictive prostheses usually consist of two parts, a metal prosthesis and a high-density polyethylene prosthesis. There is generally no need to connect the two parts, such as the head-condyle type (Ewald). This prosthesis attempts to mimic the normal anatomical relationship of the elbow joint. It is usually not used if there is a bone defect in the elbow joint or extensive damage to the joint capsule and ligament structure. Currently, there is no unified standard for evaluating the efficacy of elbow implant surgery. Morrey et al. used three indicators, namely X-ray imaging, degree of pain and range of motion, to evaluate the postoperative function of the elbow joint and divided the surgical efficacy into three levels: good, medium and poor (Table 3.16.4.2-1). In recent years, the average satisfactory rate of semi-restrictive elbow replacement surgery can reach 90%. The overall satisfactory efficacy rate of non-restrictive "surface joint replacement" is about 85%. Therefore, if the case is selected appropriately and the surgical method is correct, 90% of patients can achieve satisfactory results. Surgery related anatomy.

Contraindications

1. Those with multiple injuries throughout the body and in danger of life.

2. Recent or acute infection.

3. Neuropathic arthropathy.

4. Loss of both rotator cuff and deltoid muscle function.